Lithium iron orthosilicate, Li2FeSiO4, has increasingly become a material of interest for cathodes in lithium ion batteries due to its promising electrochemical properties demonstrated the first time by Nyten et al. and also due to the low synthesis cost compared to that of the cobalt based cathodes (Nyten 2005, 2006). A limiting factor with polyanion materials is their poor conductivity. Synthesis conditions have a large influence on the electrochemical performances of Li2FeSiO4, and many studies have been done to find out the key factor for optimized electrochemical performances. Recent trends on Li2FeSiO4 are focused on development of active materials with nano-sized particles to improve the electrochemical performance by different synthesis techniques such as solid-state, sol-gel, hydrothermal, and hydrothermal assisted sol-gel.